How long does a Female Emu stay fertile?

Merlin has been sitting on his nest of six eggs starting around the Oct 31st.....I've put some others in the bator, and Doodlebug layed another egg in the nest yesterday. I was wondering how long after breeding does the female stay fertile? I know they can lay a lot in the nest, which takes a good bit of time...... But if he's sitting on the nest for this long when will the eggs she lays stop being fertile...?

We tested whether female Emus lay fertilised eggs for a prolonged period, defined as the 'fertile period', following artificial insemination (AI) and natural mating (NM), and if so, whether the duration for which fertilised eggs are laid corresponds with the length of the period over which a clutch is laid. To determine the clutch duration, we studied the egg-laying pattern of AI females by recording oviposition and estimating oviposition interval. To determine the fertile period in NM females, we removed their male partners for 15 days and placed them in adjacent pens. The NM females laid fertilised eggs for a median duration of 11 days (range 7-14) after removal of males. For the fertile period after AI, the experiment was replicated 3 times. The mean fertile period of AI females was 16.2 ± 1.3 days, but maximum fertility was guaranteed for only 9 days. The AI females laid 6.7 ± 1.6 eggs per clutch and the oviposition interval within the clutch was 3.0 ± 0.1 days. The fertile period, estimated from the clutch size and egg interval, was 20.1 days. In conclusion, female Emus lay fertilised eggs for a prolonged time following an insemination, but their fertile period appears to be shorter than the period over which the clutch is laid

I've had them produce fertile eggs as early as march, and as late as april. So I would say in between these months, if that helps. I do have one confused female that lays down and sticks her butt in the air any time a human gets around her haha. She even tries to get the Male Rheas to breed her during the summer months, but she hates male Emus.